CyberSecBulletin
CVE-2026-11430NVD status: Deferred

grav-plugin-scheduler-webhook: Incorrect Implementation of Authentication Algorithm

CVE-2026-11430 is a high-severity incorrect implementation of authentication algorithm vulnerability in grav-plugin-scheduler-webhook from Trilby Media, with a CVSS 3.1 base score of 7.3 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, without any action from a user. The record lists version 1.1.3 as the first without the flaw, so updating grav-plugin-scheduler-webhook to that release or later removes the exposure. There is no confirmed exploitation so far. EPSS estimates a 0.96% chance of exploitation within 30 days, higher than 62% of scored CVEs.

Next patch cycle

High severity with no evidence of exploitation so far.

What to do

  1. Update grav-plugin-scheduler-webhook to 1.1.3 or a later version.
  2. Update getgrav/grav to 2.0.9 or a later version.
  3. Read the advisory on github.com for workarounds and exact fixed builds.
  4. Until you can update, restrict network access to the affected service so it is not reachable from untrusted networks.

Affected products and versions

VendorProductAffected versionsFixed in
Trilby Mediagrav-plugin-scheduler-webhookbefore 1.1.31.1.3
Trilby Mediagetgrav/gravbefore 2.0.92.0.9

Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.

How the severity score breaks down

Attack vector
NetworkCan be exploited remotely over a network, including the internet.
Attack complexity
LowNo special conditions are needed; the attack works reliably.
Privileges required
NoneNo account or login is needed.
User interaction
NoneNo action by a victim is required.
Scope
UnchangedImpact stays within the vulnerable component.
Confidentiality
LowSome restricted data can be read.
Integrity
LowLimited modification of data is possible.
Availability
LowPerformance or availability is reduced.

Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L. Scored by CNA (vulncheck.com).

Scoring systemScoreSeverityScored by
CVSS 4.06.9MediumCNA (vulncheck.com)
CVSS 3.17.3HighCNA (vulncheck.com)

Official description

Grav CMS's scheduler-webhook plugin contains an authentication bypass in the webhook token check. When the webhook feature is enabled but no webhookToken is configured, a compound conditional short-circuits and skips token validation, so an unauthenticated remote attacker who can reach POST /scheduler/webhook can trigger the operator's already-configured scheduled jobs by sending a single request. The primitive is triggering-existing-jobs, not attacker-chosen command execution: the attacker controls when the jobs run and which one runs (via ?job=), but does not control what the jobs do. Code execution follows only when the operator has configured a job that shells out, and even then the attacker controls timing rather than payload. Not a default-install issue: reaching the endpoint requires the separate scheduler-webhook GPM plugin to be installed, scheduler.modern.webhook.enabled to be true (default false), and no webhookToken to be configured; a stock Grav or Grav-Admin install exposes nothing here.

Source: the CVE record as published by its numbering authority, via NVD and CVE.org.

The underlying weakness: Incorrect Implementation of Authentication Algorithm

The requirements for the product dictate the use of an established authentication algorithm, but the implementation of the algorithm is incorrect.

More Incorrect Implementation of Authentication Algorithm vulnerabilities (CWE-303)

Timeline

  1. CVE record published.
  2. CISA published its SSVC assessment (exploitation: none, automatable: yes, technical impact: partial).
  3. Record last changed materially (score, affected products, status or references).

References

Recent Incorrect Implementation of Authentication Algorithm vulnerabilities

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